I know some people have had success with LDs during afternoon/evening naps, so maybe take a nap when the day is pretty much over for you and your kids but they aren't in bed yet. If you want to practice WBTB, rather than getting up a little early you could try waking in the middle of the night but just for 10-15 minutes, then going back to bed, I'm not sure how well that'd work though, as I've never tried that.